Personal portable electronic devices, such as cell phones, have become more popular, more important, more sophisticated, more expensive, and smaller than ever. Because of their small sizes, such devices are often lost or damaged by falling or dropping before their owners' awareness. To avoid such losses, the consumers usually pay extra for insurances or for protective accessories such as holsters or cases. However, the insurances are expensive over time and guarantee no immediate replacements by the insurance companies; the protective accessories are inconvenient and guarantee no protection for the portable devices while in use.
It is natural to apply retractable cord reels, which have been widely used for small personal items such as keys or ID badges, to securing cell phones, as disclosed in U.S. Pat. No. 5,938,137 to Poulson, U.S. Pat. No. 6,502,727 to Decoteau, and U.S. Pat. No. 7,354,304 to Livingston. One disadvantage of the retractable reels disclosed in these inventions is that their openings for exiting cord are fixed. Such feature is not suitable for cell phones, which are not only small in size but also often in use so that their position and height are frequently changed, upward and higher when in use but downward and lower when in a handbag or pocket. As a result, the cord is usually bent at the openings and thus less durable. Therefore, the retractable reels with a 360 degree-rotatable housing, as disclosed in U.S. Pat. No. 6,290,158 to Huang, U.S. Pat. No. 6,419,175 to Rankin, and U.S. Pat. No. 6,966,519 to Salentine et al., are useful for cell phones as disclosed in U.S. Pat. No. 7,665,684 to Salentine et al. and U.S. Pat. No. 7,661,620 to Fields.
One common disadvantage of all the retractable reels referenced above when used for cell phones is that if not directly tying cell phones, they cannot prevent the phones from dropping or losing but if tying the phones directly, while in use, they constantly pull the user's hand by the cord and disturb user's clothing in the cord's path, if any. Thus, the use of retractable cord reels with ratchet mechanisms, such as the one disclosed in U.S. Pat. No. 6,199,785 to Paugh, can overcome the disadvantage, as disclosed in U.S. App. Pub. No. 2005/0011982 by Salentine et al. Such retractable reels are lockable through certain mechanisms exerting some amount of force on the reels to prevent the cord from being retracted and therefore keep the cord relaxing when the cell phone is in use. However, the operation for unlocking the reels to retract is not coordinated with the normal operation of the cell phone and cannot be conveniently done by the hand holding the phone.
There are other kinds of ratchet mechanisms as disclosed for conductive or electronic cable reels in U.S. Pat. No. 6,019,304 to Skowronski et al., U.S. Pat. No. 7,364,109 to Kuo, and U.S. Pat. No. 7,384,013 to Yen, which are operable by pulling the cables. Such ratchet mechanisms can be integrated into retractable cord reels, so-called ‘single-pull’ reels, and be used for cell phones as disclosed in Chinese Pat. No. 02253321.4 to Kuo. Because their openings for exiting cord are also fixed in orientation, such retractable cord reels still have the same disadvantage as described above when applying to cell phones. To get around this, in Kuo's invention, the reel is loosely mounted to an object by a loop, a hook, or the like so that its position can vary easily with the cord around the mounting point. For the same token, however, the cord cannot be instantly retracted or pulled until whole system is adjusted and stretched against the mounting point. As a result, the retractable reel operates less smoothly for cell phones.